I accidentally harvested a Little Sister, but it had been so long since my last save that I didn't want to reload, and just kept playing. Now I've found out that apparently the game's ending changes depending on whether you harvest or rescue the Little Sisters. Will one accidental kill ruin my chances at the "good" ending?
I tried to Google this, and the various answers out there are about 50/50 "Even a single kill will change the ending" or "You have to kill at least two or three before anything changes." Because of that, I'd appreciate some kind of source for the answer if possible.
ETA: I got the good ending despite killing one little sister on the PC version of the game.